+1 on vista been pants Windows 7 is the only way
Tons of info if you google it.
http://www.vistaheads.com/forums/micros ... -down.html
Time Required: Disabling the Automatic Restart option in Windows Vista usually takes less than 10 minutes
Here's How:
1.Click on Start and then Control Panel.
Tip: In a hurry? Type system in the search box after clicking Start. Choose System from the list of results and then skip to Step 4.
2.Click on the System and Maintenance link.
Note: If you're viewing the Classic View of Control Panel, you won't see this link. Simply double-click on the System icon and proceed to Step 4.
3.Click on the System link.
4.In the task pane on the left, click the Advanced system settings link.
5.Locate the Startup and Recovery area and click on the Settings button.
6.In the Startup and Recovery window, locate and uncheck the check box next to Automatically restart.
7.Click OK in the Startup and Recovery window.
8.Click OK in the System Properties window.
9.You can now close the System window.
10.From now on, when a problem causes a BSOD or another major error that halts the system, the PC will not automatically reboot. Rebooting manually will be necessary.
You could try the above to see if that makes a difference, or try a system restore back to a time when it was fine.